The former couple, who share 4-year-old son Luca, dined at Il Pastaio in Beverly Hills. Both dressed casually for the outing, with Duff, 29, sporting jeans and a red shirt with shoulder cut-outs. She wore her hair in a half up style.
The former professional hockey player, 36, donned jeans and a grey sweater.
PEOPLE previously confirmed that Comrie is being investigated by Los Angeles police for alleged sexual battery.
While authorities could not provide further details, sexual battery involves a person touching “an intimate part of another person” without their consent, according to California law.
Comrie was later spotted out in L.A. and alone at his condo as news of the criminal investigation spread.
RELATED VIDEO: Mike Comrie, Hilary Duff’s Ex-Husband, Is Under Investigation for Sexual Battery
Duff has been open about her relationship with a new beau, singer and Matthew Koma. The duo spent Valentine’s Day in Costa Rica together, laughing and kissing on the beach.
Koma commemorated their trip with an Instagram post, showing two Polaroid-like photos: one of the beach and blue ocean, the other of her curled against his chest.
Duff later shared a snap of her own, of her and Koma kissing in the forest.
A rep Comrie did not immediately respond to PEOPLE’s request for comment.